1. Field of the Invention
The present invention relates to a laminated spiral core, a dynamo-electric-machine rotor provided therewith, and a dynamo-electric machine.
2. Description of the Related Art
Hitherto, laminated spiral cores used for rotors that are used in dynamo-electric machines such as motors or electric generators can be produced in short times by shifting positions of core division portions in the circumferential direction every time roll-up is performed by simply rolling up arc-shaped core units, which have been produced by being punched out of a hoop material, while bending the core units. Thus, the laminated spiral cores for rotors have been broadly employed as laminated cores that can be produced with an excellent productivity and that can be used for dynamo-electric machines.
Such a laminated spiral core used for a dynamo-electric machine is configured, for example, as described in Japanese Unexamined Patent Application Publication No. 2007-68310 laid open on Mar. 15, 2007.